diff --git a/PanelKit/Controller/PanelViewController.swift b/PanelKit/Controller/PanelViewController.swift
index 6f42cb4..075e827 100644
--- a/PanelKit/Controller/PanelViewController.swift
+++ b/PanelKit/Controller/PanelViewController.swift
@@ -179,6 +179,7 @@ import UIKit
 			print("\(self) viewWillAppear")
 		}
 
+        manager?.panelWillAppear(self, animated: animated)
 	}
 
 	override public func viewDidAppear(_ animated: Bool) {
@@ -191,6 +192,7 @@ import UIKit
 			print("\(self) viewDidAppear")
 		}
 
+        manager?.panelDidAppear(self, animated: animated)
 	}
 
 	override public func viewWillDisappear(_ animated: Bool) {
@@ -202,6 +204,7 @@ import UIKit
 			print("\(self) viewWillDisappear")
 		}
 
+        manager?.panelWillDisappear(self, animated: animated)
 	}
 
 	override public func viewDidDisappear(_ animated: Bool) {
@@ -213,6 +216,7 @@ import UIKit
 			print("\(self) viewDidDisappear")
 		}
 
+        manager?.panelDidDisappear(self, animated: animated)
 	}
 
 	override public func viewWillLayoutSubviews() {
diff --git a/PanelKit/Model/PanelPinSide.swift b/PanelKit/Model/PanelPinSide.swift
index 18485ec..e9194ed 100644
--- a/PanelKit/Model/PanelPinSide.swift
+++ b/PanelKit/Model/PanelPinSide.swift
@@ -16,6 +16,27 @@ import Foundation
 	case bottom
 }
 
+public extension PanelPinSide {
+    
+    public var isVertical: Bool {
+        
+        let sides: [PanelPinSide]
+        
+        sides = [.top, .bottom]
+        
+        return sides.contains(self)
+    }
+    
+    public var isHorizontal: Bool {
+        
+        let sides: [PanelPinSide]
+        
+        sides = [.left, .right]
+        
+        return sides.contains(self)
+    }
+}
+
 extension PanelPinSide: CustomStringConvertible {
 
 	public var description: String {
diff --git a/PanelKit/PanelManager/PanelManager+Default.swift b/PanelKit/PanelManager/PanelManager+Default.swift
index eb5aeb8..6a5b05a 100644
--- a/PanelKit/PanelManager/PanelManager+Default.swift
+++ b/PanelKit/PanelManager/PanelManager+Default.swift
@@ -14,6 +14,10 @@ public extension PanelManager {
 	func didUpdatePinnedPanels() {
 
 	}
+    
+    func panelManager(_ manager: PanelManager, didUpdatePinnedStateFor panel: PanelViewController, side: PanelPinSide) {
+        
+    }
 
 	func enablePanelShadow(for panel: PanelViewController) -> Bool {
 		return true
@@ -50,5 +54,21 @@ public extension PanelManager {
 	var exposeOverlayBlurEffect: UIBlurEffect {
 		return UIBlurEffect(style: .light)
 	}
+    
+    func panelWillAppear(_ panel: PanelViewController, animated: Bool) {
+        
+    }
+    
+    func panelWillDisappear(_ panel: PanelViewController, animated: Bool) {
+        
+    }
+    
+    func panelDidAppear(_ panel: PanelViewController, animated: Bool) {
+        
+    }
+    
+    func panelDidDisappear(_ panel: PanelViewController, animated: Bool) {
+        
+    }
 
 }
diff --git a/PanelKit/PanelManager/PanelManager+Dragging.swift b/PanelKit/PanelManager/PanelManager+Dragging.swift
index 3a68408..f0ecd6d 100644
--- a/PanelKit/PanelManager/PanelManager+Dragging.swift
+++ b/PanelKit/PanelManager/PanelManager+Dragging.swift
@@ -137,6 +137,8 @@ extension PanelManager {
 			self.panelContentWrapperView.layoutIfNeeded()
 
 			self.didUpdatePinnedPanels()
+            
+            self.panelManager(self, didUpdatePinnedStateFor: panel, side: side)
 
 		}, completion: { (_) in
 
@@ -281,6 +283,8 @@ extension PanelManager {
 			self.panelContentWrapperView.layoutIfNeeded()
 
 			self.didUpdatePinnedPanels()
+            
+            self.panelManager(self, didUpdatePinnedStateFor: panel, side: side)
 
 		}, completion: { (_) in
 
diff --git a/PanelKit/PanelManager/PanelManager+Pinning.swift b/PanelKit/PanelManager/PanelManager+Pinning.swift
index 9f601d3..1559401 100644
--- a/PanelKit/PanelManager/PanelManager+Pinning.swift
+++ b/PanelKit/PanelManager/PanelManager+Pinning.swift
@@ -411,6 +411,8 @@ public extension PanelManager {
 		self.panelContentWrapperView.layoutIfNeeded()
 		
 		self.didUpdatePinnedPanels()
+        
+        self.panelManager(self, didUpdatePinnedStateFor: panel, side: side)
 		
 		// Send panel and preview view to back, so (shadows of) non-pinned panels are on top
 		self.panelContentWrapperView.insertSubview(panelView, aboveSubview: self.panelContentView)
diff --git a/PanelKit/PanelManager/PanelManager.swift b/PanelKit/PanelManager/PanelManager.swift
index 597dc76..1ff24b6 100644
--- a/PanelKit/PanelManager/PanelManager.swift
+++ b/PanelKit/PanelManager/PanelManager.swift
@@ -57,6 +57,12 @@ public protocol PanelManager: class {
 	/// This will be called when a panel is pinned or unpinned.
 	/// The default implementation is an empty function.
 	func didUpdatePinnedPanels()
+    
+    /// This will be called when a panel is pinned or unpinned.
+    /// The default implementation is an empty function.
+    func panelManager(_ manager: PanelManager,
+                      didUpdatePinnedStateFor panel: PanelViewController,
+                      side: PanelPinSide)
 
 	/// Drag insets for panel.
 	///
@@ -77,6 +83,22 @@ public protocol PanelManager: class {
 	/// Called when exposé is about to be exited.
 	/// The default implementation is an empty function.
 	func willExitExpose()
+    
+    /// Called when panel is about to appear.
+    /// The default implementation is an empty function.
+    func panelWillAppear(_ panel: PanelViewController, animated: Bool)
+    
+    /// Called when panel is about to disappear.
+    /// The default implementation is an empty function.
+    func panelWillDisappear(_ panel: PanelViewController, animated: Bool)
+    
+    /// Called when panel has appeared.
+    /// The default implementation is an empty function.
+    func panelDidAppear(_ panel: PanelViewController, animated: Bool)
+    
+    /// Called when panel has disappeared.
+    /// The default implementation is an empty function.
+    func panelDidDisappear(_ panel: PanelViewController, animated: Bool)
 
 }